A CTD, to measure conductivity, temperature and density of seawater, is deployed from research vessel Oceanus during a harmful algal bloom cruise. The CTD is the primary tool for determining essential physical properties of seawater. (Photo by Maureen Lynch, Colgate University)

Kerry Norton (left) and Bruce Keafer of WHOI analyze samples in the lab during a May 2005 cruise aboard R/V Oceanus. The pair are using a molecular method called Sandwich Hybridization Assay (SHA) that identifies Alexandrium fundyense based on probes that bind to its specifc rRNA sequences. (Photo by Mike Carlowicz, Woods Hole Oceanographic Institution)

Harmful Algal Bloom (Red Tide) Models and Forecasts to be Expanded in Gulf of Maine

New Program Could Reopen Valuable Offshore Shellfish Beds

A new observation and modeling program focused on the southern Gulf of
Maine and adjacent New England shelf waters could aid policymakers in
deciding whether or not to re-open, develop, and manage offshore
shellfish beds with potential sustained harvesting value of more than
$50 million per year. These areas are presently closed to the harvest
of certain species of shellfish due to the presence of red tide toxins.

Researchers at the Woods Hole Oceanographic
Institution (WHOI) and colleagues from seven other universities or agencies began the five-year Gulf
of Maine Toxicity program, or GOMTOX, on September 1. The $7.5
million dollar program is funded by a grant from the National Oceanic
and Atmospheric Administration‘s (NOAA) National Ocean Service, Center
for Sponsored Coastal Ocean Research (NOS/CSCOR) through the ECOHAB
program.

The new research effort expands past studies in the Gulf of Maine and
builds on data collected during the historic 2005 red tide,
which led to closure of both nearshore shellfish beds and offshore beds
in federal waters out to Georges Bank. The toxicity also extended for the first
time to the islands of Martha’s Vineyard and
Nantucket.

The Gulf of Maine (GoM) and its adjacent southern New England shelf is
a vast region with extensive shellfish resources, large portions of
which are frequently contaminated with paralytic shellfish poisoning
(PSP) toxins produced by the dinoflagellate Alexandrium fundyense. The 2005 outbreak caused millions of dollars in economic damage, but
monitoring programs and cooperation among federal, state and local
officials, scientists, and shellfishermen prevented any reported cases of illness
from people eating contaminated shellfish.

“As a result of the 2005 bloom
and the closures in federal waters offshore and on the Cape and
Islands, we realized we needed to expand efforts and develop a
full, regional-scale understanding of Alexandrium fundyense
blooms,” lead
investigator Don Anderson of WHOI said.
“We don’t understand the linkages between bloom dynamics and toxicity
in waters near shore versus the offshore, nor do we know how
toxicity is delivered to the shellfish in
those offshore waters. An additional
challenge is the need to expand modeling and forecasting capabilities
to include the entire region, and to transition these tools to
operational and management use.”

Anderson said the information and new technologies gained from the
project will help managers, regulators and the shellfish industry to
fully utilize and effectively manage both nearshore and offshore
shellfish resources, and could lead to harvesting of the offshore
surfclam and ocean quahog beds on Georges Bank and Nantucket Shoals,
which have an estimated potential value of more than $50 million a
year. The program should also provide information crucial to the
development of a roe-on scallop industry in those waters - a product
which is presently restricted because of toxin that accumulates in the
roe.

GOMTOX will utilize a combination of large-and small-scale survey
cruises, autonomous gliders, moored instruments and traps, drifters,
satellite imagery and numerical models. Researchers will incorporate
field observations into a suite of numerical models of the region for
hindcasting and forecasting applications for both near shore and
offshore shellfish resources.

In addition to WHOI researchers, scientists participating in GOMTOX
represent Canada’s
Department of Fisheries and Oceans, NOAA’s Northeast Fisheries Science
Center, the Canadian National Research Council, the U.S. Food and Drug Administration, University of Maine,
University of Massachusetts, and the Stellwagen Bank National Marine
Sanctuary.

“We will be working closely with federal, state and local officials,
resource managers and shellfishermen to synthesize results and
disseminate the information and technology,” Anderson said. “Our
ultimate goal is to transition scientific and management tools to the
regulatory
community for operational use. This project covers the entire
Gulf fo Maine, including the Bay of Fundy, so there are many affected
user groups, communities, and industries who stand to benefit.”

Originally published: October 16, 2006

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